Samsung Electronics Company Limited on Wednesday unveiled a new Galaxy Note smartphone with a curved screen and iris-recognition technology, seeking to build on the sales momentum that has helped it roar back to surging profit growth.

Samsung, the world's top smartphone maker, saw its January-June mobile profit jump 49 per cent from a year earlier, thanks to robust sales of its flagship Galaxy S7 devices as well as a line-up overhaul that ditched unpopular models for fewer but more attractive new mid-to-low tier products.

The South Korean firm is betting the new big-screen device - the Galaxy Note 7 - will help sustain its mobile business revival through the second half, though new launches from rivals like Apple Inc will likely steal some of the thunder.

Samsung is using a 5.7-inch, curved screen display for the Galaxy Note 7. The new device employs a similar design to the Galaxy S series, but offers a larger screen and functions involving a pen accessory. Grip on the device was also improved to make it easier to be used with one hand.

The firm didn't disclose pricing, but said sales will begin in a first group of markets on August 19 without saying exactly where.

The new smartphone is a successor to last year's flat-screen Galaxy Note 5, but the firm opted to skip a digit and give it the number 7 to make numbering consistent with the latest version of the Galaxy S which began selling in March.

Researcher Strategy Analytics said the curved-screen Galaxy S7 edge was the world's best-selling Android smartphone during the first half of this year. Samsung hopes the new curved-screen Note phone will enjoy a similar appeal.

The Note 7 also features an iris scanner, allowing users to unlock the device through the recognition of their eyes – the first such application for a Samsung smartphone. The firm earlier this year announced a tablet device with the feature for India.

The Galaxy Note 7 will also be compatible with Samsung Pay, a mobile payments service that competes with Apple Pay, among others, which Samsung hopes will help boost margins for its devices and set its products apart from other Android phones.

Samsung also unveiled a new version of its Gear VR virtual reality headset with upgraded features such as improved viewing angles. Company executives say promotional activities pairing a VR device with the Galaxy S7 phones helped boost sales this year.